Phototherapy is known and may take the form of applying light with one or more selected wavelengths to a subject's body to treat a condition or obtain a cosmetic effect. Examples are treatment for (neonatal) jaundice and psoriasis. In the art, methods and devices are sought to improve therapeutic efficiency.
WO 2004/033040 provides devices for modulating the efficacy and/or increasing the efficiency of treatment of disease and/or cosmetic conditions through photobiostimulation combined with heating and/or cooling of the treatment region. In one aspect, these devices are directed to modulating the efficacy of photobiostimulation in a target region by controlling the temperature in the region and/or its surrounding volume. According to some other aspects of the disclosed device, tissue is heated such that bio stimulation is applied to tissue that is hyperthermic. Alternatively, portions of the target region can be cooled to selectively target bio stimulation to a specific region at a desired depth below the skin surface. A feedback mechanism is also provided so that the temperature of the target region can be selectively and accurately controlled. The device may comprise a source of electromagnetic radiation generating radiation suitable for heating the target region so as to enhance the efficacy of bio stimulation. To achieve photobiostimulation without hyperthermia a cooler, a cryogenic spray, or vaporizing cream is used.
However, inducing hyperthermia or hypothermia in tissue may be difficult to control accurately and it may not be available for certain groups of patients, e.g. patients with sensitive or damaged skin. It may also result in undesired side effects such as pain and tissue damage, in particular when a feedback mechanism for the temperature control malfunctions. The effects of hypothermia can be both negative and positive. Further, it has been found that clinical test results of photobiostimulating therapy are frequently inconclusive, which may be related to poor temperature control.
An improved method and device are therefore desired.